Do 12-month filters work well?

September 25, 2010|BILL WARD Star Tribune (Minneapolis)

Q. Are so-called 12-month furnace filters worth the cost? Do they really last that long, or is it more efficient and better to change the filter more frequently, using less- expensive filters? A. If the touted 12-month filter fits into a standard 1-inch slot, it might not work effectively over time, said Bruce Boerner, an energy efficiency engineer at Xcel Energy. "It will most likely get too dirty and the airflow will be reduced significantly over the 12 months," he said. To be viable for 12 months, a filter would need to be 3 to 4 inches deep, he said.